Study of a New Discarding Policy in ATM Networks

Abstract

為了達成非同步傳輸網路中不同類別傳輸服務的需求，這篇論文中提中一種新型的封包拋棄策略以改善封包遺失率。這個新型的封包拋棄策略使用一個動態門欄以控制交換器中丟棄封包的行為。門欄值主要是依據各種不同封包的到達率及緩衝區的剩餘空間而決定。本文中並提出一種數學分析模式以計算封包遺失率，根據研究的結果，本文所提出的新型封包拋棄策略能動態的根據交通流量及剩餘緩衝區空間調整丟棄封包的方式，而達到符合各類別的傳輸服務需求。In order to achieve the quality of service for different classes of traffic in ATM networks, a new cell-discarding scheme is proposed to improve the cell loss rate in ATM networks. In the proposed scheme, a dynamic threshold is used to control the behavior of cell discarding in the ATM switch. The value of threshold is decided dynamically according to the arrival rate of traffic and size of empty space in the buffer. Performance of the proposed cell-discarding scheme is analyzed and compared. According to the results, the performance of the proposed cell-discarding scheme can achieve the cell loss rate of the high priority class of traffic and provide better quality of service for the low priority class of traffic.